xen/grant-table: Force to use v1 of grants.

We have the framework to use v2, but there are no backends that actually use it. The end result is that on PV we use v2 grants and on PVHVM v1. The v1 has a capacity of 512 grants per page while the v2 has 256 grants per page. This means we lose about 50% capacity - and if we want more than 16 VIFs (each VIF takes 512 grants), then we are hitting the max per guest of 32. Oracle-bug: 16039922 CC: [email protected] CC: [email protected] Signed-off-by: Konrad Rzeszutek Wilk <[email protected]> Reviewed-by: David Vrabel <[email protected]>
jackyding2679 · Jan 6, 2014 · 11c7ff1 · 11c7ff1
1 parent 4e903a2
commit 11c7ff1
Showing 1 changed file with 2 additions and 4 deletions.
diff --git a/drivers/xen/grant-table.c b/drivers/xen/grant-table.c
@@ -1184,10 +1184,8 @@ static void gnttab_request_version(void)
 	int rc;
 	struct gnttab_set_version gsv;
 
-	if (xen_feature(XENFEAT_auto_translated_physmap))
-		gsv.version = 1;
-	else
-		gsv.version = 2;
+	gsv.version = 1;
+
 	rc = HYPERVISOR_grant_table_op(GNTTABOP_set_version, &gsv, 1);
 	if (rc == 0 && gsv.version == 2) {
 		grant_table_version = 2;